A Critical Role Of FMRI Combined With VBM In Evaluating The Abnormality Of Alertness And Brain Structure In Temporal Lobe Epilepsy

Objective Combining the behavior test with the method of task-based fMRI and VBM,we discuss the characteristics of the damage of alertness and brain structure in temporal lobe epilepsy(TLE),as well as the relation between them.Methods A total of 21 TLE patients and 19 healthy controls all underwent behavior exercises and tests,event-design fMRI and 3D structural images scanning.Behavior data was analyzed by software SPSS 16.MRI Data was analyzed by software SPM 8 and Rest 1.8.Results 1.Patients with TLE show significant longer RT(638.03±78.81)than controls(584.26±88.33)in double clue condition(t=2.035,P<0.05).The alertness effect RT,however,presents no significant difference between the TLE group and the healthy control(HC)group(t=0.011,P>0.05).2.(1)The fMRI of HC group shows activation of bilateral temporal lobe,right frontal lobe,right parietal lobe,bilateral occipital lobe and cerebellum(P<0.05).(2)For TLE groups,bilateral temporal lobe,right frontal lobe,left occipital lobe were prominently activated,but the range and strength of whole activation is smaller than HC group,and no activation can be found in parietal lobe and cerebellum(P<0.05).(3)Inter-group analysis: Less activation can be found in right parietal lobe(right inferior parietal lobule),right occipital lobe,left temporal lobe and cerebellum in TLE groups when compared with HC control in two independence sample t-test(P<0.05,Alphasim Correction,Voxel>152).3.As for VBM,group analyses spot that there is significant decreases in gray matter volume(GMV)in right insular,right temporal lobe,right olfactory cortex,left precuneus,left calcarine gyrus and left temporal lobe in TLE patients(P<0.05,Alphasim Correction,Voxel >228).4.The activation intensity of right inferior parietal lobule has a negative relation with the alertness effect RT(r=-0.449,P<0.05).Conclusion 1.The decrease in alerting function is possibly based on the weak activation in alertness network in TLE patients.2.Right inferior parietal lobule is the important node in alerting network.3.Patients with TLE show less gray matter volume(GMV)mostly in hippocampal area(parahippocampal gyrus)and extra-hippocampal areas such as olfactory cortex of right frontal lobe,left occipital lobe and left cuneus.4.The encephalic region of decreased alerting function in TLE patients are mainly in parietal lobe and occipital lobe,most are far from the mesial temporal lobe.Whereas the loss of GMV is mostly distributed over temporal lobe and frontal lobe nearby.They are less overlap.